Manketou'ebo Fm
Type Locality and Naming
It was named by the No. 2 Regional Survey Party under the Geological Bureau of Liaoning Province in 1974, and was first cited publicly by the Compiler
Jingeng Sha (coordinator) Group for the Regional Stratigraphic Chart of Liaoning Province. The naming section is located in the Manketou’ebo Mt of the Kundu-Lengsumu area of Ari region, Zhalute Banner, Zhelimu League, Inner Mongolia, with its reference section being situated at the Hulubu Nor of the Yuanbaoshan Animal Farm, Keshketang Banner, Chifeng City. Lower formation in this regional version of the Xinganling Gr.
Synonym: （满克头鄂博组）
Lithology and Thickness
Composed essentially of grey, grey-white, grey-yellow, and grey-violet acid volcanic rocks and volcanoclastics, intercalated with intermediate-acid volcanic rocks, volcanoclastics and volcaniclastic sediments, with a thickness of 197-2348 m.
Relationships and Distribution
Lower contact
It is in an unconformable contact with the underlying Xinmin Fm or Paleozoic strata
Upper contact
It is in a conformable contact with the overlying Manitu Fm
Regional extent
The formation is found to occur in the areas north of the Xilamulun River, and west of the Wengniute Banner, including most part of the Zhelimu League, and northern and southwestern parts of Chifeng City.
GeoJSON
Fossils
In the Manketou’ebo section it yields bivalve fossils such as Ferganoconcha subcentralis, F. curta, F. elongata, plant fossils as represented by Ginkgo sp., Lycopodites sp., Cladophlebis sp., Otozamites sp., Zamites sp., Baiera gracilis, Phoenicopsis sp., Schizolepis sp., Strobilites sp., Carpolithus sp., Coniopteris sp. and Taeniopteris sp., as well as insect fossils such as Ephemeropsis trisetalis.
Age
Depositional setting
Additional Information
Age:
The Rb-Sr whole-rock isochron age for the formation is of 160.29±4.39 Ma (Balin Left Banner). Schematic strat column suggests Oxfordian age.
Age span:
Beginning stage: Oxfordian
Fraction up in beginning stage: 0.0
Beginning date (Ma):
Ending stage: Oxfordian
Fraction up in ending stage: 0.75
Ending date (Ma):
Depositional setting:
Depositional-pattern:
Additional Information
Compiler
Jingeng Sha (coordinator)